关键词: 高精度磁法, 磁异常, 铁矿勘查

Abstract: To address the issues of insufficient coverage and limited abnormal data in the early explo ⁃ ration of the Nanqi iron mining area in Lingqiu County，it is necessary to clarify the spatial distribution， extension characteristics，and deepening patterns of the magnetite deposits，in order to provide scientific guidance for subsequent geological exploration.The study employed ground high-precision magnetic mea ⁃ surement technology，setting up a dense measurement network to collect magnetic anomaly data.At the same time，upward extension processing was used to eliminate shallow interference and highlight deep min ⁃ eral body information.The inversion method of human-computer interaction was applied to conduct quantita ⁃ tive analysis of the magnetic anomalies.Through detailed data processing and systematic analysis，5 signifi⁃ cant magnetic anomaly areas were successfully delineated.Among them，the 5#anomaly area is distributed in a north-westward direction，with a length of approximately 650 m and a width of 100 ~370 m.The anoma⁃ ly center has a ΔT ≥20 000 nT.The ore body is mainly distributed in the uplifted end of the anticline struc ⁃ ture and its two wings.The ore body is stable and concentrated，with a large extension，and has a certain scale.The C4 anomaly is caused by the relatively concentrated，parallelly arranged，deep and extended magnetite ore bodies that are inclined towards the south-west.Although it is a low-amplitude anomaly，it is actually the eastward extension of the northern anomaly belt due to the folding and structural influence of the iron-bearing rock strata.The 1#~3#anomaly areas have relatively smaller scales and shorter extensions. Comprehensive studies have shown that the high-precision magnetic survey technology can effectively iden ⁃tify the spatial distribution patterns of deep magnetite ore bodies，and the delineated anomaly areas pro ⁃ vide a reliable basis for the selection of iron ore exploration targets.It is recommended to prioritize the drill⁃ ing verification of the 5#anomaly area，laying the foundation for the estimation of the resource quantity and development planning of the mining area.

Key words: high-precision magnetic method, magnetic anomaly, iron ore exploration